Optix V5 AF Confirm Chip
I install Magic Lantern hackware and it gave me couple more MF assist features such as
1. Focus Peaking, 2. Magic Zoom window.
I used it in Live view. Actually work, the only problem is that the feature came on-off from time to time. I have to turn on the camera and turn it back on to activate the feature.
This should probably be in a Magic Lantern thread, but just to tie it up: When I lose focus peak (and I use it for the Samyang 85mm f1.4 so this may help the original poster) I find that I just need to press the Info button on my 60D a few times to scroll through the screens and it's back. Not sure if that may help.